Photon Focus MV-D1024E CameraLink Series User Manual page 22

4 Functionality
Simultaneous readout mode (exposure time < readout time) The frame rate is given by the
readout time. Frames per second equal to the invers of the readout time.
Simultaneous readout mode (exposure time > readout time) The frame rate is given by the
exposure time. Frames per second equal to the invers of the exposure time.
The simultaneous readout mode allows higher frame rate. However, If the exposure time
strongly exceeds the readout time, then the effect on the frame rate is neglectable.
In simultaneous readout mode image output faces minor limitations. The overall
linear sensor reponse is partially restricted in the lower gray scale region.
When changing readout mode from sequential to simultaneous readout mode
or vice versa, new settings of the BlackLevelOffset and of the image correction
are required.
Sequential readout
By default the camera continuously delivers images as fast as possible ("Free-running mode")
in the sequential readout mode. Exposure time of the next image can only start if the readout
time of the current image is finished.
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Figure 4.2: Timing in free-running sequential readout mode
When the acquisition of an image needs to be synchronised to an external event, an external
trigger can be used (refer to Section 4.6 and Section 5.4). In this mode, the camera is idle until
it gets a signal to capture an image.
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Figure 4.3: Timing in triggered sequential readout mode
Simultaneous readout (interleave exposure)
To achieve highest possible frame rates, the camera must be set to "Free-running mode" with
simultaneous readout. The camera continuously delivers images as fast as possible. Exposure
time of the next image can start during the readout time of the current image.
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Figure 4.4: Timing in free-running simultaneous readout mode (readout time> exposure time)
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